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Drop Chance Formula:
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The drop chance formula calculates the cumulative probability of obtaining at least one drop in n attempts in RuneScape 3. It's based on the principle of complementary probability, where we calculate the chance of NOT getting the drop in all attempts and subtract from 1.
The calculator uses the probability formula:
Where:
Explanation: The formula calculates the probability of getting at least one successful drop by first finding the probability of NOT getting the drop in all attempts (1-p)^n, then subtracting this from 1.
Details: Understanding drop probabilities helps RuneScape players estimate how many attempts they might need for rare items, plan their gameplay time, and set realistic expectations for obtaining specific drops.
Tips: Enter the single drop probability (p) as a decimal between 0-1 (e.g., 0.01 for 1% chance), and the number of attempts (n) as a positive integer. Both values must be valid.
Q1: What does the result represent?
A: The result (P) represents the probability of obtaining at least one drop after n attempts, expressed as a decimal between 0-1.
Q2: How do I convert percentage to decimal?
A: Divide the percentage by 100. For example, 5% becomes 0.05, 0.1% becomes 0.001.
Q3: Does this formula account for multiple drops?
A: No, this formula calculates the probability of getting AT LEAST ONE drop. It doesn't calculate the probability of getting exactly one drop or multiple drops.
Q4: Are drop chances independent in RuneScape?
A: Yes, most drop mechanics in RuneScape 3 use independent probabilities, meaning each attempt has the same chance regardless of previous results.
Q5: What's the 50% probability point?
A: The number of attempts needed for a 50% chance is approximately n = ln(0.5)/ln(1-p). For a 1% drop chance, this is about 69 attempts.